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Answer key · for teachers

Charts to read and discuss

Figures as of November 12, 2026, from each chart's current data.

Chart 1 of 3 · Food and drug safety

How many food recalls are for undeclared allergens each year?

The chart's answer: The FDA classified 190 food recalls in 2025 for an allergen left off the label, such as milk, peanuts, tree nuts, wheat, soy, eggs, fish, shellfish or sesame; the most since 2013 was 282 in 2017. From 2013 through 2025, undeclared allergens were the most common reason food was recalled. A recall counts once however many products it covers, in the year FDA first listed it in its weekly Enforcement Report. Chartly sorted FDA's written reasons by their key words; a recall for a germ as well counts under the germ. Meat, poultry and most egg products are USDA's to recall and aren't included. The newest allergen recalls, this year's included, are listed below.

Key numbers (Food recalls for undeclared allergens)

Questions

  1. In one sentence of your own, what does this chart show?

    Open question: answers will vary. Look for answers that use the chart's numbers and source.

  2. Find the biggest change or difference in the chart. What might explain it?

    • 2013 to 2025: up 36 (+23%)
    • Biggest rise from one point to the next: 40, 2022 to 2023
    • Biggest drop from one point to the next: 78, 2018 to 2019
  3. Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?

    • Newest: 190 in 2025
    • Source: U.S. Food and Drug Administration, Enforcement Reports (openFDA food recall data), data as of November 4, 2026

Source: U.S. Food and Drug Administration, Enforcement Reports (openFDA food recall data) (Public domain (U.S. government work); source U.S. Food and Drug Administration, openFDA) · Data as of Nov 4, 2026 · chart.ly/charts/food-allergen-recalls-per-year

Chart 2 of 3 · Climate

How much has the US warmed since 1895?

The chart's answer: The contiguous US averaged 54.6°F in 2025. The warmest year since records began in 1895 was 2024, at 55.5°F. Through 2025, the dashed trend line, the straight line that best fits every year, rose about 0.18°F a decade, or 2.3°F since 1895, and warming had sped up to about 0.5°F a decade since 1970. Alaska and Hawaii aren't included.

Key numbers (Average temperature, °F (contiguous U.S.))

Questions

  1. Find the warmest and coolest years on the chart. How many degrees apart are they?

    • Highest: 55.48 (2024)
    • Lowest: 50.05 (1917)
  2. Why might one year be much cooler than the year before, even while the trend line keeps rising?

    • 1895 to 2025: up 4.29 (+9%)
    • Biggest rise from one point to the next: 2.72, 1920 to 1921
  3. The axis doesn't start at zero here, but bar charts always do. Why is that fair for temperatures but not for bars?

    • First on the chart: 50.33 in 1895

Source: NOAA National Centers for Environmental Information, Climate at a Glance (Public domain (U.S. government work)) · Data as of Dec 31, 2025 · chart.ly/charts/us-average-temperature

Chart 3 of 3 · World

How fast has the world come online?

The chart's answer: 73.6% of the world's people used the internet in 2025, up from 15.6% in 2005, the first year the World Bank gives a world figure. It counts people who used the internet at least once in the previous three months. The world figures are estimates by the International Telecommunication Union.

Key numbers (People using the internet, % of world population)

Questions

  1. About what share of the world was online in the first year on the chart, and in the latest year?

    • Newest: 73.6% in 2025
    • First on the chart: 15.6% in 2005
  2. Did the share grow faster in some years than others? What could have sped it up?

    • 2005 to 2025: up 58 percentage points
    • Biggest rise from one point to the next: 6.2 percentage points, 2019 to 2020
  3. Using the internet once in three months counts here. What does this number leave out about how people get online?

    Open question: answers will vary. Look for answers that use the chart's numbers and source.

Source: World Bank, World Development Indicators: Individuals using the Internet (% of population) (CC BY 4.0 (credit the World Bank)) · Data as of Dec 31, 2025 · chart.ly/charts/world-internet-use

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